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Utilnivo

Developer

Utilnivo

JSON Formatter

Format, minify, and validate JSON with optional key sorting.

No registration
  • On your device

Browse more in Developer or all tools.

Private on your device

Your information stays on your device and is not uploaded.

Related tools

What is a JSON formatter?

A JSON formatter pretty-prints minified JSON, validates syntax, and can minify output again. Handy for API responses, config files, and debugging.

Paste JSON to format it with 2-space, 4-space, or tab indentation, minify it into a single line, or sort object keys alphabetically. Invalid JSON shows a parse error with line and column when available. All processing runs on your device.

API debugging often starts with pretty-printing a minified JSON response so you can spot missing fields or wrong types. Validate before deploy when config files must parse in production—trailing commas and single quotes are common copy-paste errors.

This formatter uses JavaScript JSON semantics. Extremely large payloads can slow the editor on low-memory devices; filter or split huge arrays when possible.

Pair with JSON Compare when reviewing pull requests that touch configuration or feature-flag payloads.

Minified API responses copied from browser DevTools sometimes include HTML error pages—if parsing fails, confirm the status code was 200 before blaming the JSON.

Unicode outside the Basic Multilingual Plane (emoji in keys or values) is valid JSON—do not strip surrogate pairs when pretty-printing internationalized payloads.

Sort keys alphabetically only when your team agrees on that convention—JSON object key order is not semantically meaningful.

How to use this tool

1. Paste minified or messy JSON. 2. Click Format for readable indentation or Minify to compress. 3. Fix any syntax error the parser reports. 4. Copy the output into your editor or API client.

Worked example

Example: {"name":"Ada","roles":["admin","editor"]} becomes indented multi-line JSON with clear nesting for code review.

When to use this

  • Pretty-printing API responses during debugging.
  • Finding syntax errors before deploying config JSON.
  • Minifying JSON for production payloads.
  • Sorting keys for stable diffs in code review.

Common examples

  • Minified API response from `curl` → indented JSON for diffing against staging.
  • Invalid trailing comma in config JSON → parser error line highlighted before deploy.
  • Large nested object → collapse sections mentally after pretty-print for code review.
  • Stripe webhook payload → pretty-print to inspect nested `data.object` fields.
  • package-lock fragment → validate structure before pasting into a bug report.

Common mistakes

  • Trailing commas in JSON that JavaScript allows but JSON does not.
  • Pasting single-quoted strings from JavaScript into strict JSON.
  • Assuming formatted output is validated when only whitespace changed.
  • Sharing sensitive tokens in JSON pasted into online tools—use local tools instead.

How it works

Paste JSON to format it with readable indentation or minify it into a single line. Invalid JSON shows a parse error with line and column when available. Optional key sorting orders object keys alphabetically. Formatting works on your device.

Limitations

Invalid JSON will not format until syntax errors are fixed. Very large documents may slow the browser tab.

Privacy and file handling

Your data stays on your device and is not uploaded.

Related JSON Formatter workflows

Explore focused guides that reuse this json formatter with different examples and FAQs.

FAQ

Frequently asked questions

What can I do with this tool?

You can format JSON with readable indentation, minify it into a compact single line, and optionally sort object keys alphabetically.

What happens if my JSON is invalid?

The tool shows a parse error. When the browser reports a character position, the error also includes the line and column.

Is my JSON stored?

No. Your information stays on your device and is not saved.

What is this tool?

Formats, minifies, and validates JSON for APIs, configs, and logs.

Does this run in the browser?

This tool runs in your browser. Your inputs are not uploaded to our server.

Is it free?

Yes. Free with no signup.

Is my data stored?

No. JSON stays on your device unless you copy it elsewhere.

Which related tools should I use next?

Try JSON Validator, YAML Formatter, or XML Formatter.

Part of these workflows

This tool is one step in a longer job. Jump straight to your step or open the full workflow guide.

Related pages

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